Capacitor and method for manufacturing same

ABSTRACT

A capacitor and a method for manufacturing the capacitor are provided. The capacitor comprises (1) a capacitor main body including an outer package case, an opening sealing member attached to an inside of an open portion of the outer package case and a terminal lead penetrating through the opening sealing member; (2) a base attached to an outside of the open portion of the outer package case, the base including an insertion through hole through which the terminal lead passes to be disposed on an outer side of the base; and (3) a resin layer between the base and the opening sealing member.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.16/331,247, filed on Mar. 7, 2019, which was the National Stage ofInternational Application No. PCT/JP2017/035295, filed on Sep. 28, 2017,which is entitled to the benefit of priority of Japanese PatentApplication No. 2016-189015, filed on Sep. 28, 2016, the contents ofwhich are hereby incorporated by reference.

TECHNICAL FIELD

The present invention relates to a capacitor to be mounted on a wiringboard such as a printed circuit board and relates to, for example, acapacitor having a base disposed on a side of an opening sealing memberthat seals a metal outer package case, and a method for manufacturingthe capacitor.

BACKGROUND ART

To mount a capacitor on a wiring board, for example, the capacitorincludes a base, and a mounting means is used to solder folded terminalleads that are pulled out to an outer side face of the base, to thewiring board. The capacitor used for this type of mounting is called“surface-mount capacitor”. The surface-mount capacitor has high generalversatility and is used in, for example, an automobile.

When a capacitor is disposed outdoors such as the inside of anautomobile, the environmental temperature around the position at whichthe capacitor is disposed increases. The capacitor therefore needs towithstand a high temperature environment. For example, a resin layer isformed between an opening sealing body and a base of the capacitor andthe sealability of the capacitor is thereby enhanced (see, e.g., PatentLiterature 1). According to this configuration, the heat resistance ofthe capacitor can be improved. In the capacitor having the base,insertion through holes are formed in the base and terminal leads of thecapacitor pass through the insertion through holes to be disposed on theouter side of the base.

CITATION LIST Patent Literature

Patent Literature 1: Japanese Laid-Open Patent Publication No. 6-338439

SUMMARY OF INVENTION Technical Problem

The problems to be solved by the present invention relate to thesealability of a capacitor and, for example, the present invention is tosolve at least one of the problems described in (1) to (3) below.

(1) The resin layer between the opening sealing body and the base isformed by, for example, injection of a resin after installation of thebase. In this formation of the resin layer, when the resin passesthrough the insertion through holes that are provided for the base andallow the terminal leads to pass, and outflows on the side of a contactface in contact with the wiring board of the base, the amount of theresin filling a space between the opening sealing body and the base isreduced by the amount corresponding to the amount of the outflowingresin. A problem is present that a countermeasure is necessary such asremoval of the resin outflowing to the exterior to avoid occurrence ofany defect in the mounting onto the wiring board. When the filling withthe resin is caused to discontinue at the timing at which the resin isrecognized from the insertion through holes to prevent the resin fromoutflowing from the insertion through holes, the resin mayinsufficiently fill the space between the opening sealing body and thebase, and a portion not yet filled may be generated between the openingsealing body and the base. When the amount of the filling resin issignificantly reduced, a problem arises that the sealability of thecapacitor is degraded.

(2) The sealing function of the surrounding portion of the resin layermay be more limited than that of the central portion of the resin layer.A problem arises that the limitation of the sealing function in thesurrounding portion of the resin layer between the opening sealing bodyand the base, that is, the surrounding portion of the opening sealingbody may influence the sealability of the capacitor.

(3) The resin layer between the opening sealing body and the base isformed by, for example, the injection of the resin after installation ofthe base. Any turbulence of the flow of the injected resin may cause thedischarge path through which the air between the opening sealing bodyand the base moves toward the exterior, to disappear, and thepossibility for bubbles to remain between the opening sealing body andthe base becomes high. A problem is present that excessive bubblesreduce the amount of the resin filling the space between the openingsealing body and the base, and degrade the sealability of the capacitor.Another problem is present that even bubbles not substantiallyinfluencing the sealability of the capacitor cause anxiety that thesealability of the capacitor may be degraded. From the viewpoint of thequality control of the products, a problem is present that remainder ofany bubble causing any unnecessary anxiety is disadvantageous.

Patent Literature 1 includes no disclosure and no suggestion for theabove problems and the configuration disclosed in Patent Literature 1cannot solve the above problems.

In view of the above circumstances, an object of the present inventionis to improve the sealability of a capacitor, to maintain thesealability thereof, or to suppress any degradation of the sealabilitythereof and the object of the present invention is, for example, atleast one of a first to a fourth objects.

(1) To suppress any outflowing of the resin filling the space betweenthe opening sealing body and the base (the first object).

(2) To suppress any degradation of the sealability of the capacitor bythe outflowing of the resin (the second object).

(3) To expand the sealed region of the capacitor by the resin (the thirdobject). (4) To suppress remainder of any bubble (the fourth object).

Solution to Problem

In order to achieve the above objects, a first aspect of the presentinvention is a capacitor that has a base including an insertion throughhole, the base being disposed on a side of an opening sealing member ofa capacitor main body, the opening sealing member being attached to anopen portion of an outer package case of the capacitor main body, aterminal lead of the capacitor main body penetrating through the openingsealing member and passing through the insertion through hole to bedisposed on an outer side of the base. This capacitor includes a resinlayer between the base and the opening sealing member, and the base orthe opening sealing member includes a protruding portion that isadjacent to the resin layer.

The protruding portion of the capacitor may be disposed on a faceportion on the side of the opening sealing member of the base and maysurround the insertion through hole.

The protruding portion of the capacitor may be in contact with theopening sealing member.

The protruding portion of the capacitor may include a ventilation paththat causes the insertion through hole to communicate with the resinlayer between the base and the opening sealing member.

The base of the capacitor may include a resin injection hole that isused for injection of a resin; a through hole that is used fordischarging air pushed out by the injection of the resin or for checkingthe injected resin; or the resin injection hole and the through hole.

The base of the capacitor may further include a protruding portionbetween the through hole and the resin injection hole.

The protruding portion of the capacitor may be disposed between thethrough hole and the resin injection hole.

The opening sealing member of the capacitor may include a protrudingportion on an outer side surface that faces the base. The protrudingportion of the opening sealing member maybe disposed between acircumferential portion of the base and the through hole.

The capacitor may further include a resin path formed by a space betweena tip portion of the outer package case and the base.

In order to attain the above objects, a second aspect of the presentinvention is a method for manufacturing a capacitor that has a baseincluding an insertion through hole, the base being disposed on a sideof an opening sealing member of a capacitor main body, the openingsealing member being attached to an open portion of an outer packagecase of the capacitor main body, a terminal lead of the capacitor mainbody penetrating through the opening sealing member and passing throughthe insertion through hole to be disposed on an outer side of the base.This method includes forming a protruding portion on the opening sealingmember or the base; attaching the base on the side of the openingsealing member of the capacitor main body; and forming a resin layerbetween the base and the opening sealing member and causing the resinlayer to be adjacent to the protruding portion.

In the method for manufacturing a capacitor, the protruding portion maybe formed on the base when the base is formed, the protruding portionmaybe disposed on the side of the opening sealing member by attachingthe base to the capacitor main body, and the protruding portion maysurround the insertion through hole.

Advantageous Effects of Invention

According to the present invention, the sealability of a capacitor isimproved, the sealability thereof is maintained, or any degradation ofthe sealability thereof is suppressed. For example, at least any one ofthe following effects is achieved.

(1) The base includes the protruding portion on the circumference of theinsertion through hole, and any outflowing of the resin from theinsertion through hole can thereby be suppressed.

(2) The resin can permeate between the opening sealing member and thebase by the suppression of the outflowing of the resin, and highsealability can thereby be acquired. Though the possibility ofevaporation of the electrolytic solution becomes high due to an increaseof the temperature, the evaporation of the electrolytic solution can besuppressed and the capacitor can be used in a high temperatureenvironment. Any degradation of the capacitor life due to theevaporation of the electrolytic solution can be suppressed.

(3) The capacitor includes the resin path formed by the space betweenthe base and the tip portion of the outer package case, and thearrangement region of the resin is thereby expanded to be between theouter side of the tip portion of the outer package case and the base,and the sealability of the capacitor can thereby be enhanced.

(4) The capacitor includes the protruding portion, remainder of anybubble can thereby be suppressed, any degradation of the sealability ofthe capacitor can be suppressed, and the reliability can therefore bemaintained.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a cross-sectional diagram of an example of a capacitoraccording to a first embodiment.

FIG. 2 is a cross-sectional diagram of an example of a capacitor thatincludes support protruding portions.

FIGS. 3A to 3C are diagrams of an example of a base of the capacitor.

FIGS. 4A and 4B are perspective diagrams of the base and a diagram of anexample of a flow of a resin.

FIG. 5 is a diagram of a modification example of a protruding portion ofthe base.

FIGS. 6A and 6B are diagrams of an example where a through hole isformed in a terminating portion of an injection path for the resin.

FIGS. 7A and 7B are perspective diagrams of a base of a capacitoraccording to a second embodiment and a diagram of an example of the flowof the resin.

FIGS. 8A and 8B are perspective diagrams of a base of a capacitoraccording to a third embodiment and a diagram of an example of the flowof the resin.

FIG. 9 is a diagram of an example of adjustment of the flow of theresin.

FIG. 10 is a perspective diagram of a base of a capacitor according to amodification example.

FIG. 11 is a diagram of a base of a capacitor according to amodification example and an example of the flow of the resin.

FIGS. 12A and 12B are cross-sectional diagrams of an example of acapacitor according to a fourth embodiment and a diagram of an exampleof the flow of the resin.

FIGS. 13A and 13B are diagrams of an example of an outer side surfaceand a cross-section of an opening sealing member.

FIGS. 14A and 14B are diagrams of an outer side surface and across-section of an opening sealing member according to a modificationexample.

FIG. 15 is a diagram of a base according to another embodiment.

FIG. 16 is a diagram of a base according to another embodiment.

FIG. 17 is an exploded perspective diagram of a capacitor according toanother embodiment.

MODES FOR CARRYING OUT THE INVENTION

The problems to be solved by an embodiment of this application relate tothe sealability of a capacitor. For example, a resin layer between anopening sealing body and a base is formed by, for example, injecting aresin after the installation of the base. In this formation of the resinlayer, when the base includes insertion through holes for terminal leadsto pass therethrough and a resin passes through this insertion throughholes and outflows on the side of a contact face of the base whose thecontact face is to be contact with a wiring board, the amount of theresin filling a space between the opening sealing body and the base isreduced corresponding to the amount of the outflowing resin. A problemis present that a countermeasure is necessary such as removal of theresin outflowing to the exterior to avoid occurrence of any defect inthe mounting onto the wiring board. When the filling by the resin isdiscontinued at the timing at which the resin is recognized through theinsertion through holes to prevent the resin from outflowing from theinsertion through holes, the resin may not sufficiently fill the spacebetween the opening sealing body and the base, and a portion not yetfilled may be generated between the opening sealing body and the base.When the amount of the filling resin is significantly reduced, a problemarises that the sealability of the capacitor is degraded. In view ofthese problems, an object of an embodiment of this application is, forexample, to suppress any outflowing of the resin filling the spacebetween the opening sealing body and the base, or to suppress anydegradation of the sealability of the capacitor due to the outflowing ofthe resin. The base includes a protruding portion on the circumferenceof the insertion through holes, and an effect is thereby achieved thatany outflowing of the resin from the insertion through holes can besuppressed. The resin can permeate between the opening sealing memberand the base by the suppression of the outflowing of the resin, and aneffect is achieved that high sealability can be acquired. Though thepossibility of evaporation of the electrolytic solution becomes high dueto an increase of the temperature, the evaporation of the electrolyticsolution can be suppressed and an effect is achieved that the capacitorcan be used in a high temperature environment. An effect is achievedthat any degradation of the capacitor life due to the evaporation of theelectrolytic solution can be suppressed.

For example, the sealing function of a circumferential portion of theresin layer may be more limited than that of the central portion of theresin layer. A problem is present that the limitation of the sealingfunction in the circumferential portion of the resin layer between theopening sealing body and the base, that is, the circumferential portionof the opening sealing body may influence the sealability of thecapacitor. In view of this problem, an object of an embodiment of thisapplication is to, for example, expand the sealed region of thecapacitor by the resin. The capacitor includes a resin path formed by aspace between the base and the tip portion of the outer package case,the arrangement area of the resin is thereby expanded up to a spacebetween the outer side of the tip portion of the outer package case andthe base, and the sealability of the capacitor can thereby be enhanced.

For example, the resin layer between the opening sealing body and thebase is formed by, for example, the injection of the resin after theinstallation of the base. Any turbulence of the flow of the injectedresin may cause a discharge path through which the air between theopening sealing body and the base moves toward the exterior, todisappear, and the possibility for bubbles to remain between the openingsealing body and the base is increased. A problem is present thatexcessive bubbles reduce the amount of the resin filling the spacebetween the opening sealing body and the base, and degrade thesealability of the capacitor. A problem is present that even bubbles notsubstantially influencing the sealability of the capacitor cause anxietythat the sealability of the capacitor may be degraded. From theviewpoint of the quality control of the products, a problem is presentthat remainder of any bubble causing any unnecessary anxiety isdisadvantageous. In view of the above problems, an object of anembodiment of this application is to, for example, suppress remainder ofany bubble. The base includes a protruding portion, remainder of anybubble can thereby be suppressed, any degradation of the sealability ofthe capacitor can be suppressed, and the reliability can be maintained.

First Embodiment

A first embodiment of the present invention will be described withreference to FIG. 1 to FIG. 4B. FIG. 1 is a cross-sectional diagram ofan example of a capacitor according to the first embodiment.

A capacitor 2 is an example of an electronic part and is, for example,an electrolytic capacitor or an electric double-layer capacitor. Thecapacitor 2 includes a capacitor main body 4, a base 6, and a resinlayer 8. The capacitor main body 4 can be used alone as a capacitor. Thecapacitor main body 4 includes an outer package case 10, a capacitorelement 12, and an opening sealing member 14. The capacitor element 12is sealed up in the outer package case 10 and the opening sealing member14 is attached to an opening of the outer package case 10.

The outer package case 10 is an aluminum case having a bottomedcylindrical shape. The capacitor element 12 is a wound element formed bywinding an anode foil, a cathode foil and separators to be sandwichedbetween the anode foil and the cathode foil, and has terminal leads 16-1and 16-2 are pulled out from the same face of the element. Thiscapacitor element 12 is impregnated with an electrolytic solution. Theopening sealing member 14 is formed by a rubber such as an insulatingrubber.

The terminal leads 16-1 and 16-2 of the capacitor element 12 penetratethe opening sealing member 14 into which a curling-processed open end ofthe outer package case 10 bites. The curling-processed open end of theouter package case 10 and the opening sealing member 14 form an openingsealing portion of the capacitor main body 4.

The base 6 is disposed on the opening sealing portion of the capacitormain body 4. The base 6 is disposed on the side of the opening sealingmember 14 of the capacitor main body 4. The base 6 is formed by aninsulating plate of an insulating synthetic resin or the like. Thisinsulating synthetic resin has heat resistance to the extent that theinsulating synthetic resin can withstand the heating applied when thecapacitor is mounted on the wiring board and is, for example, apolyester-based resin such as polybutylene terephthalate (PBT),polybutylene naphthalate (PBN), and polyethylene terephthalate (PET), apolyamide-based resin such as nylon, polyphenylene sulfide (PPS),polyphenylene oxide (PPO), a urea resin, a liquid crystal polymer (LCP),a phenol resin, or an epoxy resin.

The pair of terminal leads 16-1 and 16-2 protruding from the capacitormain body 4 penetrate a pair of insertion through holes 18-1 and 18-2formed in the base 6 respectively, and are pulled out to the outer sideof the base 6. A protruding portion 20 surrounding the insertion throughholes 18-1 and 18-2 is disposed on the circumference of these insertionthrough holes 18-1 and 18-2. This protruding portion 20 faces theopening sealing member 14, and isolates the resin layer 8 adjacent tothe protruding portion 20 and the insertion through holes 18-1 and 18-2from each other. The base 6 includes a circumferential wall 22 in thecircumferential portion of the base 6. The circumferential wall 22 isdisposed on the outer side of the open end of the outer package case 10and surrounds the open end.

The height of the protruding portion 20 is set to be, for example, anelevation difference H between the outer surface of the opening sealingmember 14 and the open end of the outer package case 10. When the heightof the protruding portion 20 is set to be the elevation difference H,the open end of the outer package case 10 and the base 6 are in contactwith each other and the protruding portion 20 of the base 6 and theopening sealing member 14 are in contact with each other. The outerpackage case 10 and the protruding portion 20 function as a supportingportion, and the installation of the base 6 is thereby stabilized andthe capacitor main body 4 is supported by both of the circumferentialportion and the central portion. The protruding portion 20 in contactwith the opening sealing member 14 can suppress any intrusion of theresin that forms the resin layer 8 into the insertion through holes 18-1and 18-2 at a high level. In this case, a flow path for air is formed bya small gap between the opening sealing portion of the capacitor mainbody 4 and the base 6.

The height of the protruding portion 20 may be lower or may be higherthan the elevation difference H. The protruding portion 20 lower thanthe elevation difference H can suppress any intrusion of the resinforming the resin layer 8 into the insertion through holes 18-1 and18-2. A gap is formed between the protruding portion 20 and the openingsealing member 14, and can form a flow path for air to the insertionthrough holes 18-1 and 18-2 of the base 6. The protruding portion 20higher than the elevation difference H is in contact with the openingsealing member 14 and can suppress any intrusion of the resin that formsthe resin layer 8 into the insertion through holes 18-1 and 18-2 at ahigh level. A gap is formed between the open end of the outer packagecase 10 and the base 6, and can form a flow path for air.

The resin layer 8 is disposed on the outer side of the protrudingportion 20, on the inner side of the open end of the outer package case10, and between the base 6 and the opening sealing member 14. The resinlayer 8 causes the capacitor main body 4 and the base 6 to adhere toeach other and, together with the base 6, seals the opening sealingportion of the capacitor main body 4. The resin forming the resin layer8 is, for example, a sealing resin that seals the opening sealingportion and is in a liquid form for the filling while the resin ishardened after the filling. For the filling, the gap between thecapacitor main body 4 and the base 6 is filled with the liquid-formresin and, after the filling, the resin is hardened to form the resinlayer 8. The resin forming the resin layer 8 has an affinity for thebase 6, the outer package case 10, and the opening sealing member 14,has a blocking property against any gas, and advantageously has a linearexpansion coefficient that is close to the linear expansion coefficientof aluminum (about 23×10⁻⁶/° C.), a small contraction amount forhardening, and non-hygroscopicity. The resin is, for example, an epoxyresin, an alkyd-based resin, a urethane resin, a thermosetting resin, ora UV-curable resin. The epoxy resin may be, for example, a two-componentepoxy resin using an acid anhydride or may be a one-component epoxyresin.

The terminal leads 16-1 and 16-2 are formed by a highly electricallyconductive metal. The terminal lead 16-1 is an anode side terminal,includes a lead portion pulled out from the anode foil of the capacitorelement 12 and a terminal portion to be mounted on the wiring board 24,and is formed by connecting these portions to each other by welding orthe like to integrate with each other.

The terminal lead 16-2 is a cathode side terminal, includes a leadportion pulled out from the cathode foil of the capacitor element 12 anda terminal portion to be mounted on the wiring board 24, and, same as orsimilar to the terminal lead 16-1, is formed by connecting theseportions to each other by welding or the like to integrate with eachother. Each lead portion has, for example, a columnar shape and eachterminal portion is flattened on the side of its mounting face for itscross-section to have a rectangular shape.

The terminal portions of the terminal leads 16-1 and 16-2 are eachfolded in a direction opposite to that of each other respectively alongguide grooves 26-1 and 26-2 formed on the base 6, to be disposed in theguide grooves 26-1 and 26-2 of the base 6. In this configuration, thebase 6 regulates the arrangement of the terminal leads 16-1 and 16-2 andfunctions as a terminal board of the capacitor 2. Instead of the guidegrooves 26-1 and 26-2, guide protrusions may be disposed on the side ofthe mounting face to the wiring board 24 of the base 6. In this case,the terminal portions of the terminal leads 16-1 and 16-2 are eachfolded in a direction opposite to that of each other along the guideprotrusion formed on the base 6. The guide protrusions guide theterminal portions of the terminal leads 16-1 and 16-2, and can securethe stability of the capacitor 2 for its mounting by being disposed onthe circumference of the folded terminal leads 16-1 and 16-2.

As depicted in FIG. 2, the base 6 may include support protrudingportions 202 on the side more internal of the base 6 than thecircumferential wall 22. This support protruding portions 202 are anexample of protruding portions that support the tip portion of the outerpackage case 10, are in contact with the resin layer 8, and arediscontinuously formed at positions for the base 6 to be in contact withthe tip portion of the outer package case 10. In the portion for thesupport protruding portions 202 to be formed, a first portion of the tipportion of the outer package case 10 is in contact with the supportprotruding portions 202 of the base 6. In the portion for the supportprotruding portions 202 to be divided, a second portion of the tipportion of the outer package case 10 is separate from the base 6 andgaps are formed between the tip portion of the outer package case 10 andthe base 6. The gaps between the tip portion of the outer package case10 and the base 6 form resin paths 201 to cause the resin to flow into agap between the circumferential wall 22 of the base 6 and the outercircumferential face of the outer package case 10.

The resin passes through the gaps between the outer package case 10 andthe base 6, and reaches between the circumferential wall 22 and theouter circumferential face of the outer package case 10 with theinclusion of the support protruding portions 202. The resin fills aspace between the circumferential wall 22 and the outer package case 10and a space between the base 6 and the tip portion of the outer packagecase 10, and the sealability of the capacitor 2 by the resin can beenhanced.

In the case where the base 6 includes the support protruding portions202, as depicted in FIG. 2, the height of the protruding portion 20 isset to be, for example, a height Hα acquired by adding the height of thesupport protruding portions 202 to the elevation difference H. When theprotruding portion 20 is set to have the height Hα, an advantage can beacquired that is same as or similar to that with the protruding portion20 having the elevation difference H without the support protrudingportions 202. The protruding portion 20 may be lower or may be higherthan the height Hα.

As depicted in FIG. 2, the curling-processed open end of the outerpackage case 10 maybe separate from the opening sealing member 14. Inthe case where the open end of the outer package case 10 is set to beseparate from the opening sealing member 14, for example, the openingsealing member 14 is fixed by swaging the side face of the outer packagecase 10. When the open end of the outer package case 10 is separate fromthe opening sealing member 14 and a gap is formed therebetween, theresin can be injected from this gap onto the inner side of thecurling-processed open end of the outer package case 10 and thesealability is further improved. The open end of the outer package case10 is arranged in the resin layer 8, the outer package case 10 and theresin layer 8 are thereby further integrated with each other, and thefixation strength between the resin layer 8 and the outer package case10 is improved.

FIG. 3A to FIG. 4B will be referred to for the base 6. FIG. 3A is a plandiagram of the base 6 and depicts a face portion that is a main bodyinstallation face to be disposed on the capacitor main body 4 and thatis on the side of the opening sealing member of the base 6. FIG. 3Bdepicts a cross-section taken along B-B in FIG. 3A. FIG. 3C is a bottomdiagram of the base 6 and depicts a opposite face to the main bodyinstallation face. The opposite face is an outer side face of the base6. FIG. 4A is a perspective diagram of the base 6 and FIG. 4B depictsthe flow of the resin. An arrow depicted in FIG. 4B depicts theinjection path of the resin. In the base 6 depicted in FIG. 3A to FIG.4B, the support protruding portions 202 are omitted, while the base 6may include the support protruding portions 202.

It is assumed that an imaginary line L1 connecting the insertion throughhole 18-1 and the insertion through hole 18-2 of the base 6 and amidpoint O of the insertion through hole 18-1 and the insertion throughhole 18-2 are present as depicted in FIG. 3A. A resin injection hole 28is formed on a central line L2 that passes through the midpoint O andthat is perpendicular to the imaginary line L1. The resin injection hole28 is an example of the insertion through hole that is used forinjection of a resin, and is formed at equal distances from theinsertion through holes 18-1 and 18-2. The inner side face of thecircumferential wall 22 has a circular shape to match with the outercircumference of the outer package case 10 that has the bottomedcylindrical shape. The inner side face of the circumferential wall 22may be larger than the outer circumference of the outer package case 10.In this case, as depicted in FIG. 2, the resin may fill the spacebetween the circumference of the outer package case 10 and thecircumferential wall 22. Setting as above can further maintain thesealability or the airtightness.

The facing face portion of the protruding portion 20 faces the resininjection hole 28 and includes a retreat portion 30 having an arc shapeand flat portions 32-1 and 32-2 arranged on the right and the left ofthe retreat portion 30. The outer edge portion of the protruding portion20 other than the facing face portion is formed in an arc shape that isconcentric with the circle formed by the circumferential wall 22. Anopening 34 is formed in a middle portion of the outer edge portionhaving the arc shape and on the central line L2 away from the resininjection hole 28, and a retreat portion 36 connected to the opening 34is formed on the inner side of the protruding portion 20. The retreatportion 36 has an oval shape.

The retreat portion 30 guides the resin injected from the resininjection hole 28 rightward and leftward relative to the central line L2by the arc shape thereof. The retreat portion 30 is retreated toward theside of the midpoint O, the arrangement range of the resin can therebybe expanded. The flat portions 32-1 and 32-2 guide the resin rightwardand leftward relative to the central line L2 and thereby suppress anyintrusion of the resin into the insertion through holes 18-1 and 18-2.As depicted in FIG. 4B, the outer edge portion formed in the arc shapeguides the resin such that the resin flows on the outer side of theinsertion through holes 18-1 and 18-2, and thereby suppresses anyintrusion of the resin into the insertion through holes 18-1 and 18-2.The outer edge portion has the arc shape, the outer edge portion canthereby smoothly guide the resin injected from the resin injection hole28 along the injection path for the resin depicted in FIG. 4B to theback face side of the insertion through holes 18-1 and 18-2. The opening34 and the retreat portion 36 expand the arrangement range of the resin.The protruding portion 20 and the circumferential wall 22 are formed tobe symmetric in the right-and-left direction about the central line L2,and the resin injected from the resin injection hole 28 can therebysymmetrically flows in the right-and-left direction about the centralline L2.

A portion of the protruding portion 20 is disposed on a circumferentialportion of a terminating portion 204 that the resin finally reaches inthe resin injection, and between the terminating portion 204 and theresin injection hole 28. The protruding portion 20 suppresses anystraightforward reaching of the resin injected from the resin injectionhole 28 to the terminating portion 204, and suppresses any filling ofthe terminating portion 204 by the resin before the resin fullypermeates from the resin injection hole 28 to the portion separatetherefrom. The protruding portion 20 secures the time period up to thetime when the resin fills the terminating portion 204 and suppressesremainder of any air in the vicinity of the terminating portion 204. Thesuppression of the remainder of any air enhances the sealability of thecapacitor 2. The protruding portion 20 is advantageously disposed tosurround 50% or more of the circumference of the terminating portion204, and is desirably disposed to surround 66% or more thereof. To allowthe resin to flow into the terminating portion 204, a portion of theterminating portion 204 such as, for example, 10% of the circumferenceof the terminating portion 204 is not surrounded by the protrudingportion 20 and is opened.

As depicted in FIG. 3B, the circumferential wall 22 may be higher thanthe protruding portion 20, may have the equal height as that of theprotruding portion 20, or may be lower than the protruding portion 20.As depicted in FIG. 3C, the guide grooves 26-1 and 26-2 extendingoutward from the insertion through holes 18-1 and 18-2 are formed on theouter side face of the base 6. The guide grooves 26-1 and 26-2 aresymmetrically arranged in the right-and-left direction about the centralline L2.

[Manufacturing Steps for Capacitor]

The manufacturing steps for the capacitor are an example of the methodfor manufacturing the capacitor of the present invention, and themanufacturing steps include a forming step for the capacitor main body4, a forming step for the base 6, an attaching step of attaching thebase 6 to the capacitor main body 4, a shaping step for the terminalleads 16-1 and 16-2, and an injection step for the resin.

At the forming step for the capacitor main body 4, the separator issandwiched between the anode foil to which the terminal lead 16-1 isconnected and the cathode foil to which the terminal lead 16-2 isconnected and these components are wound to form the capacitor element12. The capacitor element 12 is impregnated with the electrolyticsolution and the capacitor element 12 is sealed up in the outer packagecase 10. The opening sealing member 14 is thereafter attached to theopening portion of the outer package case 10 to form the capacitor mainbody 4. The outer package case 10 is formed from, for example, aluminum.

At the forming step for the base 6, the base 6 having the abovedescribed shape is formed from an insulating synthetic resin. In thisembodiment, the electrolytic capacitor is formed by impregnating thecapacitor element 12 with the electrolytic solution while the formationof the capacitor is not limited to this and a solid electrolyticcapacitor may be formed using the capacitor element 12 whose solidelectrolyte layer is formed by being impregnated with a conductivepolymer. A hybrid capacitor maybe employed that is formed byimpregnating the capacitor element 12 already impregnated with aconductive polymer, with an electrolytic solution.

At the attaching step for the base 6, the terminal leads 16-1 and 16-2of the capacitor main body 4 are caused to penetrate the insertionthrough holes 18-1 and 18-2 of the base 6. The base 6 is moved to attachthe base 6 to the side of the opening sealing member of the capacitormain body 4. At the attaching step, the protruding portion 20 of thebase 6 is disposed on the side of the opening sealing member.

At the shaping step for the terminal leads 16-1 and 16-2, the terminalleads 16-1 and 16-2 are folded along the guide grooves 26-1 and 26-2 ofthe base 6 and the terminal portions of the terminal leads 16-1 and 16-2are arranged in the guide grooves 26-1 and 26-2. The base 6 is fixed tothe capacitor main body 4 by performing this shaping step.

At the injection step for the resin, the liquid-form resin injected fromthe resin injection hole 28 of the base 6 fills the gap between thecapacitor main body 4 and the base 6. The injected resin forms the resinlayer 8 between the capacitor main body 4 and the base 6. For example, adispenser is used for the injection of the resin.

Characteristic items, advantages, modification examples, or the likewill be listed below for the first embodiment.

(1) The above capacitor 2 can cope with the demands such as downsizingof an electronic device and improvement of the efficiency of the surfacemounting thereof on the wiring board 24.

(2) In the above capacitor 2, the protruding portion 20 formed on thebase 6 guides the liquid-form resin injected from the resin injectionhole 28 and smooth filling by the resin of the gap between the capacitormain body 4 and the base 6 can be realized. The base 6 and the resinlayer 8 enhance the sealability of the capacitor, and an evaporationsuppressing structure for the electrolytic solution can be realized. Asa result, a specific life of the capacitor can be acquired even when thecapacitor is used in a high temperature environment.

(3) In the above capacitor 2, the protruding portion 20 of the base 6can suppress any outflowing of the resin from the insertion throughholes 18-1 and 18-2, any degradation and any dispersion of the injectedamount of the resin can be suppressed, and the quality of the capacitorcan be set to be uniform. When the resin outflows from the insertionthrough holes 18-1 and 18-2, an upward pushing force is applied to theterminal leads 16-1 and 16-2. In the above capacitor 2, however, theoutflowing of the resin is suppressed, the resin does not thereby pushupward the terminal leads 16-1 and 16-2, it is suppressed that portionsof the terminal leads 16-1 and 16-2 to be soldered with the wiring board24 leaves the mounting face to the wiring board 24 of the base 6, andthe folding property of the terminal leads 16-1 and 16-2 can beimproved.

(4) The above capacitor 2 includes the evaporation suppressing structurefor the electrolytic solution by the base 6 and the resin layer 8, theopening sealing member 14 that is thin can thereby be used and demand ofdownsizing of the capacitor 2 or reducing the height thereof can becoped with.

(5) As depicted in FIG. 2, the base 6 includes the support protrudingportions 202 on the more internal side than the circumferential wall 22,the tip portion of the outer package case 10 can thereby be separatefrom the base 6 in the dividing portion between the support protrudingportions 202 and the gap can be formed between the outer side face ofthe outer package case 10 and the base 6. The resin spreads through thisgap and the sealability of the capacitor 2 can be enhanced. The supportprotruding portions 202 may be formed on the tip portion of the outerpackage case 10 to form the gap. The support protruding portions 202 onthe side of the base 6 can integrally be formed with the base 6 when thebase 6 is formed. The load of forming the support protruding portions202 can be suppressed.

(6) The portion of the protruding portion 20 is disposed between theterminating portion 204 for the resin injection and the resin injectionhole 28, remainder of any air in the vicinity of the terminating portion204 can thereby be suppressed, any degradation of the sealability of thecapacitor 2 can be suppressed, and the reliability of the sealabilitycan be maintained.

(7) The materials to form the base 6, the resin layer 8, the outerpackage case 10, and the opening sealing member 14 are each not limitedto the above material and may be changed as necessary. It is preferredthat the base 6 is transparent or translucent and the resin layer 8 iscolored. The base 6 can be made transparent or translucent by using, forexample, a polycarbonate (PC) resin. The filling state of the resin canbe checked through the outer side face of the base 6 by using this base6 and this resin layer 8.

(8) The protruding portion 20 surrounds the insertion through holes 18-1and 18-2, while the shape thereof is not limited to the above shape andmay be varied as necessary. For example, as depicted in FIG. 5, thefacing face portion facing the resin injection hole 28 may include theretreat portion 30 and the flat portions 32-1 and 32-2, and the faceportion opposite to this facing face portion (the opposite face portionopposite to the facing face portion) may include the retreat portion 30and the flat portions 32-1 and 32-2 same as or similar to the facingface portion. Moreover, the protruding portion 20 may be formedsymmetrically about the imaginary line L1 and the opposite face portionopposite to the facing face portion and the facing face portion may havethe same shape. According to this protruding portion 20, the arrangementrange of the resin can be expanded without degrading its function ofsuppressing any outflowing of the resin from the insertion through holes18-1 and 18-2. The support protruding portions 202 are omitted in thebase 6 depicted in FIG. 5, while the support protruding portions 202 maybe included therein.

(9) The protruding portion 20 of the above capacitor 2 surrounds theoverall circumference of the insertion through holes 18-1 and 18-2,while the protruding portion 20 may partially be divided and aventilation path such as a groove or a through hole maybe formed in theprotruding portion 20. For example, even when the protruding portion 20adjacent to the terminating portion 204 into which the resin finallyflows in the resin injection is divided or the ventilation path isformed therein, the air pushed out by the injection of the resin can bedischarged from the divided portion or the ventilation path withoutdegrading the guiding function by the protruding portion 20 for theresin. The divided portion and the ventilation path do not need to beformed in the facing face portion of the protruding portion 20 thatfaces the resin injection hole 28. The resin flowing from the resininjection hole 28 can be prevented from flowing into the insertionthrough holes 18-1 and 18-2 by disposing the protruding portion 20 onthe resin injection hole 28 side of the edge portions of the insertionthrough holes 18-1 and 18-2, and concurrently the air pushed out by theinjection of the resin can be discharged by disposing the dividingportion or the ventilation path on the side of the edge portion of theinsertion through holes 18-1 and 18-2 away from the resin injection hole28.

(10) As depicted in FIGS. 6A and 6B, the protruding portion 20 mayinclude a through hole 38 different from the resin injection hole 28 andthe insertion through holes 18-1 and 18-2. This through hole 38 isformed in, for example, the terminating portion 204 into which the resinfinally flows in the resin injection and is used to check the resin thatreaches the terminating portion 204 along the injection path of theresin. The through hole 38 is also used to discharge the air that ispushed out by the injection of the resin, and the check of the fillingstate of the resin is facilitated by the through hole 38 and thedischarge of the air is also facilitated. The protruding portion 20 isdisposed to be present along the edge portion of the through hole 38. Itcan be suppressed by arrangement of the protruding portion 20surrounding the circumference of the through hole 38 to occur anyclogging of the through hole 38 before the resin injected from the resininjection hole 28 fills the space between the opening sealing member 14and the base 6. The resin can be caused to fill the space between theopening sealing member 14 and the base 6 suppressing the remainder ofthe air by the protruding portion 20 that surrounds the through hole 38such that the resin finally flows into the through hole 38. Theprotruding portion 20 is adjacent to the edge portion of the throughhole 38 and is not separated from this edge portion. Thus, remainder ofany bubble is suppressed between the through hole 38 and the protrudingportion 20. In the base 6 depicted in FIGS. 6A and 6B, the supportprotruding portions 202 are omitted, while the base 6 may include thesupport protruding portions 202.

(11) The resin may be caused to fill the insertion through holes 18-1and 18-2 from the outer side face of the base 6. The spaces between theinsertion through holes 18-1 and 18-2, and the terminal leads 16-1 and16-2 are filled with the resin and the sealability can further beenhanced.

(12) The resin injection hole 28 is formed in the base 6, the resin isinjected after the base 6 is disposed on the capacitor main body 4, andthe resin layer 8 is thereby formed in the above embodiment, while thesesteps maybe changed as necessary. The base 6 may be attached to the sideof the opening sealing member of the capacitor main body 4 after theresin is adhered to the capacitor main body 4 or the base 6, and theresin may fully be permeated between the capacitor main body 4 and thebase 6 for the resin to fill the gap between the capacitor main body 4and the base 6. The resin filling the gap between the capacitor mainbody 4 and the base 6 forms the resin layer 8. According to the aboveconfiguration, the resin injection hole 28 does not need to be disposed.The resin does not fill the insertion through holes 18-1 and 18-2 withthe protruding portion 20, and the base 6 can thereby easily be disposedon the capacitor main body 4.

Second Embodiment

A capacitor of this embodiment is an example of an electronic part andis, for example, an electrolytic capacitor or an electric double-layercapacitor. In this embodiment, the configuration of the capacitor mainbody 4, the configuration for the base to be disposed on the side of theopening sealing member of the capacitor main body 4, the configurationfor the resin to fill the space between the capacitor main body 4 andthe base, the material of the base, and the material of the resinforming the resin layer 8 are same as those of the first embodiment andwill not again be described.

FIGS. 7A and 7B will be referred to for a base of this embodiment. FIG.7A is a perspective diagram of the base and FIG. 7B depicts the flow ofthe resin. Arrows depicted in FIG. 7B indicate injection paths of theresin. In FIGS. 7A and 7B, same parts as those in FIGS. 3A to 4B aregiven the same reference signs. The support protruding portions 202 areomitted in a base 106 depicted in FIGS. 7A and 7B, while the base 106may include the support protruding portions 202. For the base 106depicted in FIGS. 7A and 7B, enclosures for the terminating portion byprotruding portions 120-1 and 120-2 are omitted, while the enclosuresfor the terminating portion may be formed.

The base 106 has the insertion through holes 18-1 and 18-2 formedtherein that are same as or similar to those of the first embodiment.The circumferences of these insertion through holes 18-1 and 18-2 areprovided with a pair of protruding portions 120-1 and 120-2 surroundingthe insertion through holes 18-1 and 18-2, and the protruding portions120-1 and 120-2 surround the insertion through holes 18-1 and 18-2respectively. The protruding portions 120-1 and 120-2 isolate the resinlayer 8 and the insertion through holes 18-1 and 18-2 from each othersame as or similar to that in the first embodiment. A resin path 140 forthe resin to pass therethrough is formed between the protruding portions120-1 and 129-2. The circumferential wall 22, the guide grooves 26-1 and26-2, and the resin injection hole 28 included in the base 106, and theheight of the protruding portions 120-1 and 120-2 are same as or similarto those of the first embodiment and will not again be described.

As depicted in FIG. 7A, a facing face portion of the protruding portion120-1 facing the resin injection hole 28 includes a retreat portion130-1 having an arc portion and a flat portion 32-1, and a facing faceportion of the protruding portion 120-2 facing the resin injection hole28 includes a retreat portion 130-2 having an arc shape and a flatportion 32-2. The retreat portion 130-1 and the retreat portion 130-2are portions of one arc. When the retreat portions 130-1 and 130-2 areextended each in the arc shape, these arc shapes overlap with eachother. The protruding portion 120-1 is formed to be symmetric about theimaginary line L1 and a face portion opposite to the facing face portion(the opposite face portion opposite to the facing face portion) has theretreat portion 130-1 and the flat portion 32-1 formed thereon. Theprotruding portion 120-2 is also formed to be symmetric and the oppositeface portion opposite to the facing face portion has the retreat portion130-2 and the flat portion 32-2 formed thereon.

Outer edge portions on the side of the resin path 140 of the protrudingportions 120-1 and 120-2 are flat. On the other hand, outer edgeportions (the opposite face portions) opposite to the outer edgeportions on the side of the resin path 140 are each formed to have anarc shape that is concentric with the circle formed by thecircumferential wall 22.

The retreat portions 130-1 and 130-2 each having the arc shape guide theresin injected from the resin injection hole 28 to the resin path 140.The retreat portions 130-1 and 130-2 retreat toward the side of themidpoint O, and the arrangement range of the resin can thereby beexpanded. The flat portions 32-1 and 32-2 guide the resin rightward andleftward, and suppress any intrusion of the resin into the insertionthrough holes 18-1 and 18-2. As depicted in FIG. 7B, the outer edgeportion formed in the arc shape (the opposite face portion of the outeredge portion on the side of the resin path 140) guides the resin for theresin to flow on the outer sides of the insertion through holes 18-1 and18-2, and the resin path 140 guides the resin for the resin to flowalong the central line L2. Both of these suppress any intrusion of theresin into the insertion through holes 18-1 and 18-2. The outer edgeportion has the flat or the arc shape, the outer edge portion canthereby smoothly guide the resin injected from the resin injection hole28 to the back face sides of the insertion through holes 18-1 and 18-2along the injection path of the resin depicted in FIG. 7B. Theprotruding portions 120-1 and 120-2 are symmetrically formed in theright-and-left direction, and can thereby cause the resin injected fromthe resin injection hole 28 to flow symmetrically in the right-and-leftdirection.

The steps for manufacturing the capacitor according to this embodimentare same as or similar to the steps for manufacturing the capacitoraccording to the first embodiment and will not again be described.

Characteristic items, advantages, modification examples, or the likewill be listed below for the second embodiment.

(1) The advantages same as or similar to those of the first embodimentare acquired, and same or similar modifications can be made.

(2) In the above capacitor, the resin passes on the outer side of theprotruding portions 120-1 and 120-2 and through the resin path 140, andthe resin can thereby fill in a short time period.

Third Embodiment

A capacitor of this embodiment is an example of an electronic part andis, for example, an electrolytic capacitor or an electric double-layercapacitor. In this embodiment, the configuration of the capacitor mainbody 4, the configuration for the base to be disposed on the side of theopening sealing member of the capacitor main body 4, the configurationfor the resin to fill the space between the capacitor main body 4 andthe base, the material of the base, and the material of the resinforming the resin layer 8 are same as or similar to those of the firstembodiment and will not again be described.

FIGS. 8A and 8B will be referred to for a base of this embodiment. FIG.8A is a perspective diagram of the base and FIG. 8B depicts the flow ofthe resin. Dotted lines each in a curved line form depicted in FIG. 8Beach indicate the position of the tip of the resin at one time pointduring the resin injection and indicate the state where the resinspreads. Arrows depicted in FIG. 8B indicate flows of the resin. Acircular two-dot chain line along the circumferential wall 22 in FIG. 8Bindicates the arrangement position of the curling-processed inner sideend of the outer package case 10. In FIGS. 8A and 8B, same parts asthose in FIG. 2, FIG. 3A, FIG. 3B, FIG. 3C, FIG. 4A, FIG. 4B, FIG. 6Aand FIG. 6B are given the same reference signs.

The base 206 depicted in FIGS. 8A and 8B includes, for example, foursupport protruding portions 202 on the side more internal than thecircumferential wall 22 of the base 206. The support protruding portions202 are an example of the protruding portion that is in contact with thefirst portion of the tip portion of the above outer package case 10 andsupports the tip portion. The support protruding portions 202 are formedat a position to face the tip portion of the outer package case includedin the opening sealing portion. The shape of the support protrudingportions 202 is, for example, a columnar shape and the four supportprotruding portions 202 are arranged at intervals of, for example, 90degrees relative to the midpoint of the four support protruding portions202. Two support protruding portions 202 are arranged on the outer sideof the insertion through holes 18-1 and 18-2 so that the insertionthrough holes 18-1 and 18-2 are sandwiched between the two supportprotruding portions 202. The other two support protruding portions 202are arranged on the outer side of the resin injection hole 28 and thethrough hole 38 so that the resin injection hole 28 and the through hole38 are sandwiched between the other two support protruding portions 202.The four support protruding portions 202 each face the insertion throughholes 18-1 and 18-2, the resin injection hole 28, or the through hole38.

The base 206 has the insertion through holes 18-1 and 18-2 formedtherein, and the insertion through holes 18-1 and 18-2 are same as orsimilar to those of the first embodiment. The base 206 includes a pairof protruding portions 220-1 and 220-2 (first protruding portions)surrounding the insertion through holes 18-1 and 18-2, on thecircumference of the insertion through holes 18-1 and 18-2, and theprotruding portions 220-1 and 220-2 surround the insertion through holes18-1 and 18-2 respectively. The protruding portions 220-1 and 220-2 facethe opening sealing member 14 in the same manner as that in the firstembodiment and isolate the resin layer 8 and the insertion through holes18-1 and 18-2 adjacent to the protruding portions 220-1 and 220-2, fromeach other. The resin path 140 for the resin to pass therethrough isformed between the protruding portions 220-1 and 220-2.

The base 206 includes a protruding portion 220-3 (a second protrudingportion) that is disposed on a circumferential portion of the throughhole 38 and between the through hole 38 and the resin injection hole 28.The through hole 38 is formed in the terminating portion that the resinfinally reaches in the resin injection. The protruding portion 220-3suppresses any straightforward reaching of the resin injected from theresin injection hole 28 to the through hole 38, and suppresses anyfilling of the through hole 38 by the resin before the resin fullypermeates the end portion of the region in which the resin layer 8 isformed between the opening sealing member 14 and the base 206. Theprotruding portion 220-3 surrounds a portion such as, for example, twothirds of the circumference of the through hole 38. The protrudingportion 220-3 surrounds preferably 50% or more and surrounds desirably66% or more of the circumference of the through hole 38. For example, asdepicted in FIG. 16, for example, 10% of the circumference of thethrough hole 38 may be open without being surrounded by the protrudingportion 220-3.

The protruding portion 220-3 is disposed to be present along the edgeportion of the through hole 38. The protruding portion 220-3 is adjacentto the edge portion of the through hole 38 and is not separated fromthis edge portion. Thus, remainder of any bubble is suppressed betweenthe through hole 38 and the protruding portion 220-3. The outer sidesurface of the protruding portion 220-3 facing the resin injection hole28 has a curved face such as an arc face and the resin can thereforesmoothly flow along the outer side surface of the protruding portion220-3.

The circumferential wall 22, the guide grooves 26-1 and 26-2, and theresin injection hole 28 included in the base 206, and the height of theprotruding portions 220-1 and 220-2 are same as or similar to those ofthe first embodiment and will not again be described.

As depicted in FIG. 8B, the resin injected from the resin injection hole28 spreads from the resin injection hole 28 toward the outer sidethereof. The resin spreads passing through the resin path 140 and theouter side of each of the protruding portions 220-1 and 220-2. The resinfully permeates the overall formation region for the resin layer 8,thereafter passes through the opening of the protruding portion 220-3not having the protruding portion 220-3, and reaches the through hole38. The protruding portions 220-1 and 220-2 are symmetrically formed inthe right-and-left direction, and can thereby cause the resin injectedfrom the resin injection hole 28 to flow symmetrically in theright-and-left direction.

[Adjustment of Flow of Resin]

FIG. 9 depicts an example of adjustment of the flow of the resin. InFIG. 9, the support protruding portions 202 are not depicted. Thethickness of each of the protruding portions 220-1 and 220-2 may beuniform or may be non-uniform. For example, as depicted in FIG. 9, thethickness of each of the protruding portions 220-1 and 220-2 is set suchthat an outer side thickness To of each of the protruding portions 220-1and 220-2 is smaller than an inner side thickness Ti of each of theprotruding portions 220-1 and 220-2. The outer side thickness To is thethickness of each of the protruding portions 220-1 and 220-2 close tothe outer side of the base 206, and the width of the gap between each ofthe protruding portions 220-1 and 220-2, and the circumferential wall 22is adjusted by increasing or decreasing the outer side thickness To. Theouter side thickness To adjusts a flow F1 of the resin passing betweeneach of the protruding portions 220-1 and 220-2, and the circumferentialwall 22. The inner side thickness Ti is the thickness of each of theprotruding portions 220-1 and 220-2 close to the inner side of the base206, and the width “a” of the gap between the protruding portions 220-1and 220-2, that is, the resin path 140 is adjusted by increasing ordecreasing the inner side thickness Ti. The inner side thickness Tiadjusts a flow F2 of the resin passing between the protruding portions220-1 and 220-2.

When the width “a” is small, the amount of the resin flowing along theflow F2 is small. In this case, before the resin flowing along the flowF2 reaches a region X, the resin flowing along the flow F1 runs in andreaches a region Y, and the possibility for air to remain in the regionX thereby becomes high. In contrast, when the width “a” is large, theamount of the resin flowing along the flow F2 is large. In this case,before the resin flowing along the flow F1 reaches the through hole 38,the resin flowing along the flow F2 reaches the through hole 38, and thepossibility for air to remain in the region Y thereby becomes high. Theouter side thickness To and the inner side thickness Ti may be adjustedsuch that the resin is stably injected into the region X and the regionY. Production of any capacitor having air remaining therein can besuppressed and any dispersion of the quality of the capacitor can besuppressed, by adjusting the outer side thickness To and the inner sidethickness Ti.

The steps for manufacturing the capacitor according to this embodimentare same as or similar to the steps for manufacturing the capacitoraccording to the first embodiment and will not again be described.

Characteristic items, advantages, modification examples, or the likewill be listed below for the third embodiment.

(1) The advantages same as or similar to those of the first embodimentand the second embodiment are acquired, and same or similarmodifications can be made.

(2) The support protruding portions 202 are in contact with the firstportion of the tip portion of the outer package case 10, and the gap,that is, the resin path can be formed between the second portion of thetip portion of the outer package case 10 and the base 206. The resinpasses through the gap between the second portion of the tip portion ofthe outer package case 10 and the base 206, reaches between thecircumferential wall 22 and the outer circumferential face of the outerpackage case 10, and fills the space between the circumferential wall 22and the outer package case 10 and the space between the base 206 and thetip portion of the outer package case 10. The sealability of thecapacitor can thereby be enhanced.

(3) The protruding portion 220-3 is disposed between the through hole 38and the resin injection hole 28, the through hole 38 is prevented frombeing filled by the resin before the resin fully permeates the endportion of the region in which the resin layer 8 is formed between theopening sealing member and the base 206, remainder of any air canthereby be suppressed, any degradation of the sealability of thecapacitor can be suppressed, and the reliability of the sealability canbe maintained.

(4) The number of the support protruding portions 202 is not limited tofour. One or two elongated support protruding portion(s) 202 may beformed to stably support the capacitor main body. Three or more supportprotruding portions 202 may be formed to stably support the capacitormain body at three of more points.

(5) As depicted in FIG. 10, the support protruding portions 202 may beformed on the base 206 by forming recessed portions 203. The supportprotruding portions 202 are in contact with the tip portion of the outerpackage case 10, and the recessed portions 203 can form a gap, that is aresin path between the tip portion of the outer package case 10 and thebase 206. The resin can reach between the circumferential wall 22 andthe outer circumferential face of the outer package case 10, and theresin can fill a space between the circumferential wall 22 and the outerpackage case 10 and a space between the base 206 and the tip portion ofthe outer package case 10.

(6) In the third embodiment, as depicted in FIG. 8B, the shape of theprotruding portion 220-3 is symmetrical in the right-and-left directionabout the central line that connects the center of the resin injectionhole 28 and the center of the through hole 38, while, as depicted inFIG. 11, the shape of the protruding portion 220-3 maybe asymmetric inthe right-and-left direction. The protruding portion 220-3 depicted inFIG. 11 is also disposed between the through hole 38 and the resininjection hole 28, the through hole 38 is prevented from being filled bythe resin before the resin fully permeates the end portion of the regionin which the resin layer 8 is formed between the opening sealing memberand the base 206, remainder of any air is thereby suppressed, anydegradation of the sealability of the capacitor can be suppressed, andthe reliability of the sealability can be maintained.

(7) The shape of each of the support protruding portions 202 is notlimited to the columnar shape. The shape of each of the supportprotruding portions 202 may be the shape of a polygonal prism such as atriangular prism and a quadrangular prism, may be a semispherical shape,or may be a columnar shape or a polygonal prism shape having thesemispherical shape on the top thereof.

Fourth Embodiment

A capacitor of this embodiment has outer side protruding portions 317-1and 317-2 formed on the opening sealing member 314 instead of theprotruding portion 220-3 in the third embodiment.

FIGS. 12A and 12B will be referred to for the capacitor of thisembodiment. FIG. 12A is a cross-sectional diagram of an example of thecapacitor according to the fourth embodiment, and FIG. 12B depicts theflow of the resin. Dotted lines each in a curved line form depicted inFIG. 12B indicate the position of the tip of the resin at one time pointduring the resin injection and indicate the state where the resinspreads. Arrows depicted in FIG. 12B indicate flows of the resin. InFIG. 12A, same parts as those in FIG. 2 are given the same referencesigns. In FIG. 12B, same parts as those in FIG. 8B are given the samereference signs. The support protruding portions 202 are not depictedfor the base 206 depicted in FIG. 12B. In FIG. 12A and FIG. 12B, aCartesian coordinate system is set using X, Y, and Z such that the resininjection hole 28 and the through hole 38 are lined in the X-directionand the insertion through holes 18-1 and 18-2 are lined in theY-direction.

A capacitor 302 is an example of an electro part and is, for example, anelectrolytic capacitor or an electric double-layer capacitor. Thecapacitor 302 includes a capacitor main body 304, a base 306, and theresin layer 8. The capacitor main body 304 is same as or similar to thecapacitor main body 4 of the first embodiment except the opening sealingmember 14. The capacitor main body 304 includes an opening sealingmember 314 instead of the opening sealing member 14. The opening sealingportion of the capacitor main body 304 is formed by the open end of theouter package case 10 and an opening sealing member 314.

The opening sealing member 314 includes outer side protruding portions317-1 and 317-2 on an outer side surface of the opening sealing member314. The outer side protruding portions 317-1 and 317-2 are each anexample of the protruding portion on the side of the opening sealingmember 314, are formed in a circumferential portion of the openingsealing member 314, and are arranged inside the curve that is formed atthe open end of the outer package case 10 by the curling process. Withthis arrangement, the outer side protruding portions 317-1 and 317-2fill the inside of the curve formed on the open end of the outer packagecase 10. The outer side protruding portions 317-1 and 317-2 may beintegrally formed with the main body portion of the opening sealingmember 314 or may be formed separately therefrom. Except the outer sideprotruding portions 317-1 and 317-2, the opening sealing member 314 issane as or similar to the opening sealing member 14 of the firstembodiment. As depicted in FIG. 12A, the outer side protruding portions317-1 and 317-2 are adjacent to the resin layer 8.

The base 306 is same as or similar to the base 206 of the thirdembodiment without the protruding portion 220-3.

As depicted in FIG. 12B, in the state where the capacitor main body 304is disposed on the base 306, the outer side protruding portion 317-1 isarranged in the circumferential portion of the through hole 38 and onthe side more external of the base 306 than the through hole 38, thatis, between the circumferential wall 22 formed on the circumferentialportion of the base 306, and the through hole 38. The outer sideprotruding portion 317-2 is arranged in the circumferential portion ofthe resin injection hole 28 and on the side more external of the base306 than the resin injection hole 28, that is, between thecircumferential wall 22 and the resin injection hole 28. The outer sideprotruding portions 317-1 and 317-2 are arranged on the central linethat connects the center of the resin injection hole 28 and the centerof the through hole 38.

As depicted in FIG. 12B, the resin injected from the resin injectionhole 28 spreads from the resin injection hole 28 toward the outer sidethereof. The resin spreads passing through the resin path 140 and theouter side of each of the protruding portions 220-1 and 220-2. The resinfully permeates the overall formation region for the resin layer 8 andthereafter reaches the through hole 38. The outer side protrudingportion 317-1 guides the resin on the side more external than thethrough hole 38 to the through hole 38, and the presence of the outerside protruding portion 317-1 suppresses formation of any bubble on theside more external of the base 306 than the through hole 38.

FIGS. 13A and 13B are diagrams of the opening sealing member. FIG. 13Ais a diagram of the opening sealing member seen from the outer sidesurface thereof, and FIG. 13B is a diagram of a B-B cross-section of theopening sealing member depicted in FIG. 13A. The circular two-dot chainline depicted along the circumference of the opening sealing member 314in FIG. 13A indicates the arrangement position of the curling-processedinner side end of the outer package case 10.

The outer side protruding portions 317-1 and 317-2 each include an apexportion 318 and a slope portion 320. The apex portion 318 has a flatface parallel to an outer side surface OS of the opening sealing member314 and protrudes toward the side more external than the outer sidesurface OS, that is, toward the side of the base 306. The slope portion320 includes a slope face connected to the apex portion 318 and theouter side surface OS of the opening sealing member 314. The outer sideprotruding portions 317-1 and 317-2 each has a partial truncated-cornshape formed by cutting off a portion thereof in a cylindrical shape bythe edge portion of the opening sealing member 314. The outer sideprotruding portions 317-1 and 317-2 are formed, for example,line-symmetrically about the central line that connects the centers oftwo terminal holes 322 in which the lead portions of the terminal leads16-1 and 16-2 are disposed, respectively.

At the steps for manufacturing the capacitor 302, the opening sealingmember 314 including the outer side protruding portions 317-1 and 317-2is formed, and the opening sealing member 314 is attached to the openingportion of the outer package case 10 such that the outer side protrudingportions 317-1 and 317-2 are arranged on the outer side of the capacitormain body 304. Other steps for the manufacturing are same as or similarto the steps for manufacturing the capacitor according to the firstembodiment and will not again be described.

Characteristic items, advantages, modification examples, or the likewill be listed below for the fourth embodiment.

(1) The advantages same as or similar to those of the first embodimentare acquired and same or similar modifications can be made. In the firstembodiment, the portion of the protruding portion 20 is disposed tosurround the through hole 38 and even the portion far from the resininjection hole 28 than the through hole 38 is thereby filled with theresin to suppress remainder of any air while, in the fourth embodiment,remainder of any air is suppressed by the outer side protruding portion317-1. The outer side protruding portion 317-1 is arranged on the sideof the circumferential wall 22 of the through hole 38, remainder of anyair can thereby be suppressed in the vicinity of the through hole 38present at the position farthest from the resin injection hole 28, anydegradation of the sealability of the capacitor can be suppressed, andthe reliability of the sealability can be maintained.

(2) Same as or similar to the third embodiment, the resin path can beformed by the support protruding portions 202, the resin can fill thespace between the circumferential wall 22 and the outer package case 10and the space between the base 6 and the tip portion of the outerpackage case 10, and the sealability of the capacitor can be enhanced.

(3) Same as or similar to the third embodiment, the number or the shapeof the support protruding portions 202 can be varied and modificationscan be made to the support protruding portions 202 depicted in FIG. 10.

(4) The outer side protruding portions 317-1 and 317-2 each has thepartial truncated-corn shape formed by cutting off the portion thereofin a cylindrical shape by the edge portion of the opening sealing member314 in the fourth embodiment, while the shape of each of the outer sideprotruding portions 317-1 and 317-2 is not limited to the truncated-cornshape. For example, as depicted in FIG. 14A, the border line between theapex portion 318 and the slope portion 320 and the border line betweenthe slope portion 320 and the outer side surface OS of the openingsealing member 314 may each be formed in a straight line and the outerside protruding portions 317-1 and 317-2 may each be formed in abelt-like shape. The belt-like outer side protruding portions 317-1 and317-2 fill the inside of the curve formed on the open end of the outerpackage case 10, and the outer side protruding portion 317-1 can guidethe resin present on the side more external of the base 306 than thethrough hole 38 to the through hole 38 and can suppress formation of anybubble on the side more external of the base 306 than the through hole38. Any degradation of the sealability of the capacitor can besuppressed by the suppression of the bubble and the reliability of thesealability can be maintained.

(5) The outer side protruding portions 317-1 and 317-2 may be formedasymmetrically about the central line that connects the centers of thetwo terminal holes 322. For example, the outer side protruding portion317-1 may be the outer side protruding portion 317-1 depicted in FIG.13A, and the outer side protruding portion 317-2 may be the outer sideprotruding portion 317-2 depicted in FIG. 14A.

(6) The two outer side protruding portions 317-1 and 317-2 are formed onthe opening sealing member 314 in the fourth embodiment, while the outerside protruding portion 317-2 may not be formed. When the outer sideprotruding portion 317-1 is formed on the opening sealing member 314,remainder of any bubble on the side more external of the base 306 thanthe through hole 38 can be suppressed. When the two outer sideprotruding portions 317-1 and 317-2 are formed on the opening sealingmember 314, remainder of any bubble can be suppressed by either theouter side protruding portion 317-1 or the outer side protruding portion317-2. The capacitor main body 304 can therefore be disposed on the base306 without taking into consideration the position of the outer sideprotruding portion 317-1, and the load of checking the position of theouter side protruding portion 317-1 can be reduced.

(7) The outer side protruding portions 317-1 and 317-2 are arranged onthe central line that connects the center of the resin injection hole 28and the center of the through hole 38, while the outer side protrudingportions 317-1 and 317-2 may be arranged in the vicinity of this centralline.

(8) The outer side protruding portions 317-1 and 317-2 are arrangedinside the curve formed on the open end of the outer package case 10 bythe curling process, while the outer side protruding portions 317-1 and317-2 may be arranged inside the curve and on the side more internal ofthe base 306 than the curve. Remainder of any bubble can further besuppressed by setting the outer side protruding portions 317-1 and 317-2to be close to the through hole.

(9) The outer side protruding portions 317-1 and 317-2 may be includedtogether with the protruding portion 20 described in the firstembodiment or the protruding portion 220-3 described in the thirdembodiment. The effect of suppressing any bubble is enhanced byincluding the two or more means of suppressing the remainder of anybubble.

Other Embodiments

(1) In examples described in the above embodiments, the height of eachof the protruding portions 20, 120-1, 120-2, 220-1, and 220-2 is set tobe equal to or larger than the elevation difference H, so that theprotruding portions 20, 120-1, 120-2, 220-1, and 220-2 are in contactwith the opening sealing member 14 or 314, and in other examplesdescribed in the above embodiments, the height of each of the protrudingportions 20, 120-1, 120-2, 220-1, and 220-2 is set to be smaller thanthe elevation difference H, so that the gaps are formed between theprotruding portions 20, 120-1, 120-2, 220-1, and 220-2 and the openingsealing member 14 or 314. However, the protruding portions 20, 120-1,120-2, 220-1, and 220-2 are not limited to those of the above examplesand may be changed as necessary. For example, groove portions maybeformed in the apex portion of each of the protruding portions 20, 120-1,120-2, 220-1, and 220-2 at predetermined intervals (for example, 90degrees) about the center of each of the insertion through holes 18-1and 18-2. The intervals of the groove portions are each not limited to90 degrees. For example, as depicted in FIG. 15, eight groove portions324 maybe formed at angles each of 45 degrees about the center of eachof the insertion through holes 18-1 and 18-2. The protruding portions20, 120-1, 120-2, 220-1, and 220-2 each having the groove portions 324formed thereon are brought into contact with the opening sealing member14 or 314. According to these configurations, because of the contact ofthe protruding portions 20, 120-1, 120-2, 220-1, and 220-2, and theopening sealing member 14 or 314 with each other, the stability of theinstallation of each of the bases 6, 106, 206, and 306 can be improved,the ventilation paths are formed by the groove portions 324, and the airpushed out by the injection of the resin can thereby be discharged tothe exterior through the groove portions 324. Moreover, the opening areaof each of the ventilation paths and the opening area of the overallventilation paths can be managed and adjusted by varying the width, thedepth, the installation interval, or the installation quantity of thegroove portions 324, and any intrusion of the resin can easily besuppressed admitting the passage of the air. The width, the depth, theinstallation interval, or the installation quantity of the grooveportions 324 are set as necessary taking into consideration the passageof the air and the suppression of any intrusion of the resin. Forexample, as depicted in FIG. 16, the groove portions 324 may be formedonly on the side of the opposite face portion opposite to the facingface portion that faces the resin injection hole 28 without forming thegroove portions 324 on the side of the facing face portion. The grooveportion 324 is not formed in the direction in which the resin comesflowing for a base 406 depicted in FIG. 16, the possibility for theresin to exit from the insertion through holes 18-1 and 18-2 through thegroove portions 324 can thereby be reduced and the air can be dischargedfrom the insertion through holes 18-1 and 18-2 through the grooveportions 324 formed on the side of the terminating portion that theresin finally reaches.

(2) The protruding portions 120-1 and 120-2 or the protruding portions220-1 and 220-2 surrounding the insertion through holes 18-1 and 18-2respectively are formed and the resin path is set between the protrudingportions 120-1 and 120-2 or the protruding portions 220-1 and 220-2 inthe second embodiment to the fourth embodiment, while the configurationis not limited to these. For example, as depicted in FIG. 16, a grooveportion 424 including a groove for the resin to pass therethrough may beformed on a protruding portion 420 that is formed integrally by theprotruding portions surrounding the insertion through holes 18-1 and18-2 like the protruding portion 20 in the first embodiment. This grooveportion 424 is formed by reducing the height of a portion of theintermediate portion between the insertion through hole 18-1 and theinsertion through hole 18-2, and extends between the side of the resininjection hole 28 and the side of the through hole 38 to form a resinpath. The flow amount of the resin flowing through the width a of theresin path 140 depicted in FIG. 9 can be limited by configuring asabove.

(3) The protruding portion 220-3 is adjacent to the edge portion of thethrough hole 38 in the third embodiment. However, it is only requiredthat remainder of any bubble is suppressed between the through hole 38and the protruding portion 220-3 and, as depicted in FIG. 16, the endportion of the protruding portion 220-3 may match with the edge portionof the through hole 38 so that the end portion of the protruding portion220-3 and the edge portion of the through hole 38 form one curved face.

(4) In the first embodiment to the fourth embodiment, the protrudingportions 20, 220-3, or the outer side protruding portions 317-1 and317-2 are disposed in the terminating portion 204 for the resininjection or in the circumferential portion of the through hole 38, andremainder of any air in the vicinity of the terminating portion 204 orthe through hole 38 is suppressed. However, for example, in thecapacitor 2 according to the third embodiment, a through hole may beformed in a portion of the open end of the outer package case 10, or anotch portion 326 may be formed in a portion of the open end of theouter package case 10 as depicted in FIG. 17 so that a discharge pathfor the air is formed. Remainder of the air can further be suppressed bydischarging the air from the notch portion 326 to the exterior. Thethrough hole or the notch portion 326 is applicable to the embodimentsother than the third embodiment. Remainder of any air may be suppressedby the through hole or the notch portion 326 without forming theprotruding portions 20, 220-3, or the outer side protruding portions317-1 and 317-2.

(5) The curling formed in each of the capacitor main bodies 4 and 304may not be formed. The resin injection to the outer circumference sideof the resin layer 8 can easily be controlled by not forming thecurling.

(6) Not all of the configurations of (a) to (c) described below need tobe included, so that improvement or maintenance of the sealability ofthe capacitor 2, or suppression of any degradation of the sealability isenabled by including any one of the configurations.

(a) The configuration to suppress any outflowing of the resin by theprotruding portions 20, 120-1, 120-2, 220-1, and 220-3.(b) The configuration to form the resin path by the support protrudingportions 202.(c) The configuration to suppress remainder of any air by the protrudingportions 20 and 220-3 or the outer side protruding portion 317-1.

As above, the most preferred embodiment etc. of the present inventionhave been described, while the present invention is not limited to theabove description, and those skilled in the art can naturally makevarious modifications and various changes thereto on the basis of thegist of the present invention described in the claims or disclosed inthe description. The modifications and changes are obviously included inthe scope of the present invention.

INDUSTRIAL APPLICABILITY

The capacitor and the method for manufacturing the capacitor of thepresent invention can be widely used in electronic devices and areuseful.

REFERENCE SIGNS LIST

-   2, 302 capacitor-   4, 304 capacitor main body-   6, 106, 206, 306, 406 base-   8 resin layer-   10 outer package case-   12 capacitor element-   14 opening sealing member-   16-1, 16-2 terminal lead-   18-1, 18-2 insertion through hole-   20, 120-1, 120-2, 220-1, 220-2, 220-3, 420 protruding portion-   22 circumferential wall-   24 wiring board-   26-1, 26-2 guide groove-   28 resin injection hole-   30, 36, 130-1, 130-2 retreat portion-   32-1, 32-2 flat portion-   34 opening-   38 through hole-   140 resin path-   201 resin path-   202 support protruding portion-   203 recessed portion-   204 terminating portion-   317-1, 317-2 outer side protruding portion-   318 apex portion-   320 slope portion-   322 terminal hole-   324, 424 groove portion-   326 notch portion

1. A capacitor comprising: a capacitor main body including an outerpackage case, an opening sealing member attached to an inside of an openportion of the outer package case and a terminal lead penetratingthrough the opening sealing member; a base attached to an outside of theopen portion of the outer package case, the base including an insertionthrough hole through which the terminal lead passes to be disposed on anouter side of the base; and a resin layer between the base and theopening sealing member, wherein the base further includes a resininjection hole that is used for injection of a resin, a through holethat is used for discharging air pushed out by the injection of theresin or for checking the injected resin, and a first protruding portiondisposed along a part of an edge portion of the through hole.
 2. Thecapacitor according to claim 1, wherein the first protruding portion isdisposed between the through hole and the resin injection hole.
 3. Thecapacitor according to claim 1, wherein the first protruding portion isdisposed along 50% or more of the edge portion of the through hole oralong 66% or more of the edge portion of the through hole.
 4. Thecapacitor according to claim 2, wherein the first protruding portion isdisposed along 50% or more of the edge portion of the through hole oralong 66% or more of the edge portion of the through hole.
 5. Thecapacitor according to claim 1, wherein the base or the opening sealingmember includes a second protruding portion that is adjacent to theresin layer and isolates the insertion through hole from the resinlayer.
 6. The capacitor according to claim 5, wherein the secondprotruding portion is disposed on a face portion on the side of theopening sealing member of the base and surrounds the insertion throughhole.
 7. The capacitor according to claim 5, wherein the secondprotruding portion is in contact with the opening sealing member.
 8. Thecapacitor according to claim 5, wherein the second protruding portionincludes a ventilation path that causes the insertion through hole tocommunicate with the resin layer between the base and the openingsealing member.
 9. The capacitor according to claim 1, furthercomprising a resin path formed by a space between a tip portion of theouter package case and the base.
 10. A method for manufacturing acapacitor, the method comprising: forming a capacitor main bodyincluding an outer package case, an opening sealing member attached toan inside of an open portion of the outer package case and a terminallead penetrating through the opening sealing member; forming a baseincluding an insertion through hole, a resin injection hole, a throughhole and a protruding portion disposed along a part of an edge portionof the through hole; attaching the base on an outside of the openportion of the outer package case for the terminal lead to pass throughthe insertion through hole, and disposing the terminal lead on an outerside of the base; injecting a resin through the resin injection hole,and discharging an air between the base and the opening sealing memberthrough the through hole by an injection of the resin or checking theinjected resin through the through hole; and forming a resin layerbetween the base and the opening sealing member.